The Pharmacokinetics of LEO 90105 (Calcipotriol Hydrate Plus Betamethasone Dipropionate) in Japanese Subjects With Extensive Psoriasis Vulgaris

Inclusion Criteria: * Japanese subjects having understood and signed a written informed consent form prior to any study related procedures being carried out (including activities related to the wash out period) * 20 years of age or above. * Either sex. * Clinical diagnosis of psoriasis vulgaris amenable to topical treatment involving arms and/or trunk and/or legs. * Psoriasis vulgaris on the trunk/limbs (excluding psoriasis on the genitals/skin folds) of not more than 30% body surface area (BSA) * An Investigator's global assessment of disease severity (IGA) on area(s) to be treated of moderate, severe or very severe and a m-PASI score of ≥12. * Females of childbearing potential must have a negative result for a urine pregnancy test at Day 1 (Visit 1) and must agree to use an adequate method of birth control, as judged by the (sub)investigator, during the study. The contraceptive method should have started an adequate amount of time before the pregnancy test, which is dependent on the particular method used and as judged by the (sub)investigator, and must continue for at least 1 week after the last application of study medication. A female is defined as not of child-bearing potential if she is postmenopausal (12 months with no menses without an alter-native medical cause) or surgically sterile (tubal ligation /section, hysterectomy or bilateral ovariectomy). Exclusion Criteria: * Systemic use of biological treatments with a potential effect on psoriasis vulgaris within the following time periods prior to Visit 1: * etanercept, adalimumab, infliximab -3 months. * ustekinumab - 4 months * other products - within 3 months/5 half-lives (whichever is longer). * Systemic treatments with all therapies other than biological treatments with a potential effect on psoriasis vulgaris (e.g., corticosteroids, vitamin D analogues, retinoids, immu-nosuppressants such as ciclosporin and methotrexate) within 4 weeks prior to Visit 1 (use of inhaled and nasal corticosteroids is allowed, use of systemic antihistamines is allowed). * Topical treatment of scalp psoriasis with vitamin D analogues (e.g. calcipotriol, tacalcitol, maxacalcitol), or very potent WHO group IV corticosteroids within 2 weeks prior to Visit 1. * PUVA therapy, UVB therapy or UVA therapy within 4 weeks prior to Visit 1. * Topical treatment of psoriasis on the face, genitals or skin folds with vitamin D analogues (e.g. calcipotriol, tacalcitol, maxacalcitol), or potent or very potent WHO group III or IV corticosteroids within 2 weeks prior to Visit 1. * Topical treatment of psoriasis on area(s) to be treated with study medication within the 2-week period prior to Visit 1. (Use of emollients is allowed during this 2- week period, but not during the study.) * Planned initiation of, or changes in, concomitant medication that may affect psoriasis vulgaris (e.g., beta-blockers, antimalaria drugs, lithium and ACE inhibitors) during the study. * Topical treatment of conditions other than psoriasis with vitamin D analogues (e.g. calcipotriol, tacalcitol, maxacalcitol), or potent or very potent WHO group III or IV corti-costeroids within 2 weeks prior to Visit 1. * Current diagnosis of erythrodermic, exfoliative, guttate or pustular psoriasis. * Clinical signs or symptoms of Cushing's disease or Addison's disease * Patients with any of the following disorders (a) or symptoms (b) present on the area(s) to be treated with study medication: (a) viral (e.g., herpes or varicella) lesions of the skin, fungal or bacterial skin infections, parasitic infections, skin manifestations in relation to syphilis or tuberculosis, rosacea, acne vulgaris, atrophic skin, striae atrophicae, ichthyosis, acne rosacea, ulcers, burns, frostbite, wounds, or (b) fragility of skin veins. * Other inflammatory skin diseases (e.g., seborrhoeic dermatitis, contact dermatitis and cutaneous mycosis) that may confound the evaluation of psoriasis vulgaris. * Planned excessive exposure of treated areas(s) to either natural or artificial sunlight (including tanning boths, sun lamps, etc) during the study. * Known or suspected disorders of calcium metabolism associated with hypercalcaemia (subjects with results for albumin-corrected serum calcium above the reference range from the sample taken at the Washout/Screening Visit. * Severe renal insufficiency, severe hepatic disorders or severe heart disease. * Known or suspected hypersensitivity to components of the investigational products. * Current participation in any other interventional clinical study * Subjects who have received treatment with any non-marketed drug substance (i.e. an agent which has not yet been made available for clinical use following registration) within the 4-week period prior to Visit 1 or longer, if the class of substance re-quires a longer washout as defined above (e.g. biological treatments). * Females who are pregnant, wishing to become pregnant during the study, or are breast-feeding * Patients suspected of being unable to comply with the study protocol, e.g. due to alcoholism, drug dependence or psychotic state. * Previous enrollment in this study. * Hospitalised patients.